Flat body. Prominent marginals; the supero- and inferomarginals are similar. The aboral plates are flat or paxilliform, bearing granules, low stumps or spines. Only the radial areas have papulae. Pedicellariae are generally present. The tube feet have suckers.
Click on the image below to view an expanded illustration for this taxon. If more than one illustration is available for a species (e.g., two subspecies may be illustrated) then links to the separate images will be provided below.
Ceramaster arcticus is small and pentagonal, stiff and firm to the touch, and up to 5.5 cm in greatest radius. It is pale orange with red patches. The ratio of arm to disc is 1.6. The aboral surface has tabulate plates bearing 4 to 12 marginal granules surrounding 1 to 3 smaller central granules. C. arcticus has 18 to 24 massive superomarginals, each usually with a bare spot surrounded by flat granules; the inferomarginals each have a smaller bare spot; papulae cover the aboral surface. The adambulacrals have 2 or 3 short, thick furrow spinelets with 3 to 6 granules on oral surface of the plate, which often has a bivalved pedicellaria.
Ceramaster arcticus differs from C. patagonicus in its smaller average size, fewer granules on the aboral tabulate plates and fewer adambulacral spines.
Bering Sea to the Juan de Fuca Strait; intertidal to 186 metres. Found on mud in the deep part of its range to rock in shallow waters. Rare in this region (the area from Glacier Bay to Puget Sound to a depth to 200 metres).
Recommended citation: Author, Date. Page title. In Klinkenberg, Brian. (Editor) 2021. E-Fauna BC:
Electronic Atlas of the Fauna of British Columbia [efauna.bc.ca]. Lab
for Advanced Spatial Analysis, Department of Geography, University of British
Columbia, Vancouver. [Accessed:
2022-01-18 11:38:23 AM]
The information contained in an
E-Fauna BC atlas pages is derived from expert sources as cited (with permission) in each section.
This information is scientifically based. E-Fauna BC also acts as a
portal to other sites via deep links. As always, users should refer to
the original sources for complete information. E-Fauna BC is not
responsible for the accuracy or completeness of the original information.